Trip casing spear oil-well rotary fishing tool



P. C. COREY June 24, 1930.

TRIP CASING SPEAR OIL WELL ROTARY FISHING TOOL Filed July 19, 1929 fnuenior: 1 ers a'aaZ 61%)? 3%65 Aifornfy.

Patented June 24, 1930 UNITED STATES PATENT OFFICE PERCIVAL C. COREY, OF LOS ANGELES, CALIFORNIA, ASSIGNOR OF ONE-THIRD TO JOHN G. MASSEY AND ONE-THIRD TO CHARLT ON WALLACE, JR., BOTH LOS ANGELES, CALIFORNIA TRIP CASING SPEAR OIL-WELL ROTARY FISHING TOOL Application filed July 19, 1929. SeriaI No. 379,415

This invention relates to oil well fishing tools and more particularly to a trip casing spear oil well rotary fishing tool.

The general object of the invention is to provide an improved trip casing spear oil well rotary fishing tool for fishing out lost pipe from oil wells, or for releasing the pipe when it cannot be removed by the tool, so that the tool may be removed from the well without danger of being broken or damaged.

A more particular object is to provide a fishing tool of the character stated by means of which upper sections of lost oil well pipe may be unscrewed from the lower sections and removed from the well, thus enabling the tool to remove one or more sections of the lost pipe at a time until the entire pipe is removed from the well.

Other objects and advantages will appear hereinafter as this specification progresses.

The-invention is illustrated in the annexed drawing which forms a part of this specification and in which;

Fig. 1 is a longitudinal section of my invention shown introduced into a well casing but before the spear slips are forced into spearing engagement with the casing.

Fig. 2 is a view like Fig. 1 except that the spear slips are shown in gripping engagement with the casing.

Fig. 3 is a cross section of my invention taken on line 3-3 of Fig. 1.

I Fig. 4 is a cross section of my invention taken on line 4/& of Fig. 1.

Fig. 5 is a fragmentary elevation of the lower intermediate body sections of the tool.

Corresponding parts are designated by the same reference characters in all the views.

My invention includes generally a body 1, a mandrel 2, friction springs 3 and 4, an expansible and contractible packofl ring 5 and slips 6.

The body 1 comprises a lower main section 7, a lower end spear section 8, an intermediate section 9 and ,an upper section 10, through which sections extends the mandrel 2. The lower end of the mandrel is reduced slightly and provided with a thread 11 on which, the lower end spear section 8 screws against a shoulder 12 formed on the mandrel at the upper end of the thread 11. An end thrust bearing 13 rests upon the upper end of the lower end spear section 8 and the lower main body section 7 rests upon said end thrust bearing. The friction springs 3 are flat outwardly bowed springs and have their ends fitted in vertical grooves 14. in the periphery of the lower section 7. The lower section 7 is formed with an upper reduced end 15 which is formed with upwardly projecting prongs 16. An an nular external shoulder 15 is formed on the section 7 at the base of the reduced end 15.

The intermediate body section '9 is formed with an upwardly converging conical surface 17 and with a reduced lower end 18 which end is formed with depending prongs 19 slidably fitting between the prongs 16 of the lower body section 7. An annular external shoulder 20 .is formed on the section 9 between the lower end of the conical surface 17- and the reduced lower end 18. The section 9 has an internal left thread 21 which engages a left thread 22 on the mandrel 2.

The upper body section 10 is provided with longitudinal grooves 23 in its periphery in which are fitted the outwardly-bowed fiat friction springs 4. In the lower end of the section 10 are provided recesses 24 and said section has an internal right thread 25 engaged by a right thread 26 on the mandrel 2.

A sleeve 27 slidably fits around the reduced upper and lower ends 15 and 18 of the lower section 7 and intermediate section 9 respectively, said sleeve being formed with an external annular flange 28 at its upper end which flange extends outwardly beyond the lower end of the conical surface 17 of the section 9. The packofl' ring 5 fits around the sleeve 27 between the shoulder 15', on the upper end of the lower section 7, and the flange 28 of said sleeve. 1

, The slips 6 are formed with internal conical surfaces 29, external teeth 30 external shoulders 31 at the upper end of the slips and arms 32 extending upwardly from the slips into the recess 25 in the lower end of the upper body section 10 said arms being provided with longitudinal slots 33 throughwhich extend pins 34 secured in said body section. The conical bore 29 receives the conical surface 17 of the 100 I casing 37; the friction springs 3 and 4 engaging the casing and allowing the tool to slide only slowly down the casing (See Flg. 1). The mandrel 2 is then rotated, so that the intermediate body section 9 is caused to move upwardly on the mandrel by means of the interengaging threads 21 and 22, and the upper section 10 is caused to movedownwardly on the mandrel by the interengagement of the threads 25 and 26 while the lower end of the upper section, engaging the slip shoulders "31, forces the slips 6 downwardly on the intermediate section 9, whereupon the engagement of the conical surface 17 of the section 9 with the conical slip surfaces 29, forces the slips 6 outwardly untilthe slip teeth 80 effectively engage the inner surface of the casing, and as the slips approach the end of their downward movement their lower ends engage the sleeve flange 28 and force the sleeve 2 downwardly, whereby the packoif ring 5 is compressed between the flange 28 and the shoulder 15 and is expanded into engagement with the inner surface of the casing (see Fig. 2), which seals the upper portion of the casing. Power is then applied to the mandrel to raise the easing which ordinarily may be pulled bodily out of the well.

If the entire casing cannot be pulled at once, power is applied to the mandrel to rotate the tool and casing to unscrew a joint 38 of the casing, so that an upper section of the casing may be removed. One section of the casing after another may be thus removed until the entire casing is removed.

If it should be impossible to remove the casing one way or another, the mandrel 2 may be rotated in a reverse direction so that the intermediate section 9 will be moved downwardly by the threads 21 and 22, and the upper section 10 will be moved upwardly by the threads 25 and 26, which will allow the packofl" ring 5 and the slips 6 to contract to enable the tool to be removed from the casing without being broken or damaged.

I do not limit my invention to the exact form herein disclosed because it may be embodied in other forms, and it is to be under stood that-in and by the claims of this specification I intend to cover my invention in whatever form it may be embodied.

I claim as my invention p 1. A fishing tool including a body formed with a conical section andan upper sectlon,

said sections being provided respectively with opposite screw threads, a mandrel extending through said sections and formed with threads engaging respectively the threads of said sections, slips slidable on said conical section and arranged to be engaged by said upper section when the mandrel is rotated in one direction for forcing the slips down on said conical section to expand the slips into engagement with the well casing.

2. A fishing tool including a body formed with a conical section and an upper section, said sections being provided respectively with opposite screw threads, :1 mandrel extending through said sections and formed with threads engaging respectively the threads of said sections, slips slidable on said conical section and arranged to be engaged I by said upper section when the mandrel is rotated in one direction for forcing the slips -down on said conical section to expand the slips into engagement with the well casing, and means actuated by said slips when expanded for packing oil the casing.

3. A fishing tool including a mandrel provided with opposite threads, abody comprising a lower end spear section, a lower main section, an intermediate section and an uppersection, said sections being arranged on said mandrel, with said lower end spear section secured on the lower end of the mandrel, an end thrust bearing mounted on said lower end spear section, said lower main section resting upon said end thrust bearing, friction springs on said lower main section for engaging the well casing, said intermediate section and said upper section being formed with threads engaging the threads respectively on said 'mandrel said interinediate section being formed with a conical surface, slips fitted on the conical surface of said intermediate section and arranged to be engaged by the upper section and forced downwardly on said conical surface for expanding the slips against the I casing when the mandrel is rotated in one directionto cause the threadson the mandrel and said sections to move the intermediate section up and the upper section down and friction springs on said upper section for en gaging the casing. I

4. A fishing tool includi g a mandrel provided with opposite threads, a body comprising a lower end spear section, a lowermain section, an intermediate section and an upper section, said sections being arranged on said mandrel with said lower end spear section secured on the lower end of the mandrel, an end thrust bearing mounted on said lower end spear section, said lower main section resting upon said end thrust bearing, friction springs on said lower main section for engaging the well casing, said intermediate section and said upper sectionbeing formed with threads engaging the threads respectively on said mandrel, said intermediate section being formed with a conical surface, slips fitted on the conical surface of said intermediate section and arranged to be engaged by the upper section and forced down- \vardly on said conical surface for expanding the slips against the'casing when the mandrel is rotated in one direction to cause the threads on the mandrel and said section to move the intermediate section up and the upper section down, a shoulder on the upper portion of said lower main section, a sleeve surrounding the upper end of said main sec-, tion and the lower end of said intermediate section and formed with an external flange to be engaged by said slips when forced down, a packofl ring surrounding said sleeve to be expanded against the casing when said flange is engaged by said slips, and friction springs on said upper section for engaging the casing.

2-0 PERCIVAL C. COREY. 

